How many number plates can be made if the number plates have two letters of the English alphabet followed by two digits if the repetition of digits or alphabets is not allowed?
Solve for the number of combinations of number plates
No. of English alphabets
No. of digits
We have total four place to cover with two alphabets and two digits.
_ _ _ _
(alphabet) (alphabet) (digit) (digit)
For the first place:
Out of alphabets we need one. Therefore, combinations for first place is
For the second place:
We are left with alphabets now as no repetitions are allowed.
Therefore combinations for second place is
For the third place:
Out of digits we need to select one . Therefore combinations for third place is
For the fourth place:
We are left with digits now as no repetitions are allowed. Therefore combinations for fourth place is
In order to find the total no. of possible number plate that can be made, we will multiply the combinations for each of the places. So total Combinations of number plates
Hence, the required number of plates is